I had a ton of fun learning to beat this game. It is very arcadey which I primarily see as a good thing.
There are a ton of aspects which make a lot of sense in arcade games, but are completely unfair.
Dying in one hit is way too harsh.
Especially when there is no hints as to how enemies will attack.
(New enemy attack patterns shouldn't instantly kill players that can not possibly be prepared for them.)
I personally would have preferred dying in two hits with some form of recovery mechanic.
It would still be difficult, but players would then be able to take a hit and learn from it in the same run.
As others have commented, the controls are highly unusual. A radial menu is cool and keeps the number of input devices down, but it's also slow.
Players have to drag and drop select which ships they want to command
Then they have to move the cursor again to where the ships are supposed to move/fire
Then they have to move the cursor yet again to select the desired action.
In a game that leaves such little time to react, I'd prefer the actions to be instant.
OR: if you insist on using a radial menu you can at least give the players more time to react.
However: The game being this unfair made me want to beat it more.
As I got better, the earlier levels went by quicker and the wasted time from having to start again felt tolerable.
There was always something for me to do and try. Dying gave me the instant urge to try again.
If I had to insert coins for every attempt, I'd be a poor man. Incredible job!